21100112002021 has 8 divisors (see below), whose sum is σ = 22723278195800. Its totient is φ = 19476957330432.

The previous prime is 21100112001959. The next prime is 21100112002043. The reversal of 21100112002021 is 12020021100112.

It can be written as a sum of positive squares in 4 ways, for example, as 514935408100 + 20585176593921 = 717590^2 + 4537089^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21100112002021 - 2¹¹ = 21100111999973 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a junction number, because it is equal to n+sod(n) for n = 21100112001992 and 21100112002010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100112006021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1129621 + ... + 6593653.

It is an arithmetic number, because the mean of its divisors is an integer number (2840409774475).

Almost surely, 2^{21100112002021} is an apocalyptic number.

It is an amenable number.

21100112002021 is a deficient number, since it is larger than the sum of its proper divisors (1623166193779).

21100112002021 is a wasteful number, since it uses less digits than its factorization.

21100112002021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5761095.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21100112002021 its reverse (12020021100112), we get a palindrome (33120133102133).

The spelling of 21100112002021 in words is "twenty-one trillion, one hundred billion, one hundred twelve million, two thousand, twenty-one".